Source code for langchain.output_parsers.regex

from __future__ import annotations

import re
from typing import Dict, List, Optional

from langchain_core.output_parsers import BaseOutputParser


[docs]class RegexParser(BaseOutputParser[Dict[str, str]]): """Parse the output of an LLM call using a regex.""" @classmethod def is_lc_serializable(cls) -> bool: return True regex: str """The regex to use to parse the output.""" output_keys: List[str] """The keys to use for the output.""" default_output_key: Optional[str] = None """The default key to use for the output.""" @property def _type(self) -> str: """Return the type key.""" return "regex_parser"
[docs] def parse(self, text: str) -> Dict[str, str]: """Parse the output of an LLM call.""" match = re.search(self.regex, text) if match: return {key: match.group(i + 1) for i, key in enumerate(self.output_keys)} else: if self.default_output_key is None: raise ValueError(f"Could not parse output: {text}") else: return { key: text if key == self.default_output_key else "" for key in self.output_keys }